Rock-drill valve



' Juli? 20, 1926.

1,592,849 c. c. HANSEN ROCK DRILL VALVE Filed Sept. 16. v1925 2 She ets-Sheeti I N VEN TOR.

- HIS ATTOX, I

(A {wall sen-- BY y July '20 ,1926. 1,592,849 c. c. HANSEN ROCK DRILL VALVE FiledSept. 1e 1925 2.Sheets-Sheet 2 INVENTOR.

6 02443363 men Patented July 20, 1926 UNITED STATES PATENT OFFICE.

CHARLES C, HANSEN, OF EASTON, PENNSYLVANIA, ASSIGNOR '10 INGERSOLL-RAND COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NElV JERSEY.

ROCK-DRILL VALVE.

Application filed September This invention relates to fluid actuated rock drills of the hammer type, but more particularly to a distributing valve for controlling both the inlet and exhaust of the cylinder.

The objects of the invention are to enable the valve to be efliciently actuated or thrown in one direction or the other with certainty and precision by pressure fluid under working pressure supplied to the ends of the valve chest through passages or kicker ports controlled by the piston, and effect the holding of the valve in one position or the other by means of live air alternately admitted to the ends of the valve chest through live air leak ports controlled by the valve and connected directly with the main pressure fluid supply of the rock drill. To accomplish these objects in the most efficient manner, constantly open at mospheric leak ports are also preferably provided for the ends of the valve chest.

The invention is shown in one of its preferred forms in the accompanying drawings, in which Figures 1 to 4-, inclusive, are diagrammatic longitudinal sectional views partly broken away of a rock drill showing the piston and valve in different positions in passing through the cycle of operations.

Only so much of the rock drill is shown as will serve to make the invention clear, and it is to be understood that the invention may be applied to a rock drill having automatic rotation of the rifle bar or independent type, although the automatic rotation is not shown in the drawings, for simplicity of illustration.

Referring to the drawings, the cylinder A is provided with the reciprocating piston B and the valve chest C in which the distributing valve D, preferably in the form of a spool valve, reciprocates and controls both the inlet and exhaust of the cylinder A.

The main supply port E of pressure fluid for the rock drill is in this instance, located centrally of the valve chest C, and the main exhaust ports F and G are located at each side of the main supply. The central head H of the valve controls the port E so that pressure fluid is supplied alternatclyto the ends of the cylinders through the inlet passages J and K.

The end heads L and O of the valve are of the same diameter as the central head H,

16, 1925. Serial No. 56,653.

and the valve is preferably hollow and surrounds the central bolt P, which secures the valve bushings Q in position. These valve buslnngs Q form stops for the valve.

Valve actuating ports or kicker ports, as they are usually termed, R and S connect the ends T and U of the valve chest with the central portion of the cylinder A and are controlled by the piston B for actuating the valve in one direction or the other by means of pressure fluid under Working pressure. The ends of the valve chest are vented to atmosphere by the constantly open atmospheric leak ports V and WV. These valve chest ends are also alternately supplied with live air through live air leak ports X and Y controlled by the end heads 0 and L of the valve. The leak ports X and Y lead directly to the main supply port E and are therefore constantly exposed to live pressure fluid.

In the operation of the device let itbe forward travel, as indicated by the arrow in Figure 1, in which case the valve is in its forward position. Pressure fluid is admitted from the main supply port E around the valve and through the passage J to the rearward end of the cylinder to drive the piston forward. Live air supplied through the live air leak port X holds the valve in its forward position, it being understood that the atmospheric port W is preferably of somewhat smaller cross sectional area than the kicker port S to prevent the pressure at the rearward end of the valve from being reduced to atmospheric pressure before the valve is ready to be thrown rearwardly.

The forward end T of the valve chest is at atmospheric pressure through the atmospheric vent port V and the live air leak port Y at the forward end of the cylinder is cut oil and closed by the forward end L of the valve.

The forward end of the cylinder A exhausts through the passage K and around the valve to the main exhaust port F. The rearward end U of the valve chest is also open to exhaust through the kicker port S and passage K and exhaust port F, but it will be observed that the space Z between the valve chest and either one of the valve bushings Q is so restricted that the holding. pressure, when desired, against one end face or the assumed that the piston is starting on its other of the valve is maintained for a sulficient length or time for the operation of the piston.

As the piston B travels on its forward stroke and uncovers the kicker, port R, as indicated in Figure 2, pressure fluid under working pressure is supplied through said kicker port to the forward end 1 of the valve chest, ano as the pressure in the rearward end U of the valve chest has by this time become reduced through leakage, the pressure at the forward end ottho valve chest on the valve preponderates and causes the valve to he thrown rearwardly to the position indicated in Figure 2. T he tor-ward end L of the valve opens the live air leak port Y and admits live air for holding the valve in its rearward position, while the rearward end head G of the valve closes the live air leak port X, so that therearward end of the valve chest is substantially at atmospheric pressure while the valve is being held in rearward position. Figure 8 illustrates the piston after it has started on its rearward travel, as indicated by the arrow, and has reached a position substantially midway in the cylinder covering both kicker ports R and S while tie valve is still held in its rearward position because of the live air admitted through the live air leak port Y to the forward end of the valve chest. The valve does not flutter and the piston does not become centered in the cylinder owing to the construction and arrangement'o'f the ports and passages and their control. In Figure the piston is shown on its rearward travel over-running the kicker port S, in which case pressure fluid under working pressure admitted to the rearward end U of the valve chest and the valve is thrown to its :t'orward position which opens the live air leak port X, as in Figure l, and closes the live air leak port Y. From this position the cycle is repeated, and it is to be under- .stood that the inlet passage J becomes an exhaust passage for the rearward end or the cylinder as the piston travels rearwardly.

I claim:

1. In a fluid actuated rock drill, the comhination of a cylinder and reciprocating pi ton, a valve chest having a main supply port, a distributing valve in said valve chest eonthe ends of the valve chest to points near the center of the cylinder for actuating the valve, constantly open atmospheric leak ports or the ends of the valve chest, and live air leak ports for the ends oi the valve chest in constant communication with the main supply port and controlled by the end heads of the valve, whereby the valve is actuated by pressure fluid under workingp ssure alternately supplied through the said kicker ports and held after actuation by live air admitted through one or the other of the said live air leak ports.

2. In a iiuid actuatedrock drill, the combination of acylinder and reciprocating piston, a valve chest having a central n'iain sup-- ply port and live air leak ports leading to the ends at the valve chest said leak ports being constantly exposed to pres ar re tluid, comrant open atmospheric leak ports for the ends oi the valve chest, combined inlet and exhaust passages leading from the central portion of the valve chest to the ends of the cylinder, main exhaust po ts 1" r sai valve chest, piston controlled crssed kicker leading from the ends of the valve chest to points inthe cylinder interin-edla"v the said combined inlet and exhaust pasand a spool valve in said che" having a Cclli al head and end heads all 0 the same diameter, the cc ral head controll' the simply of pressure liuid to said combined 'es, and the end heads inlet and exhaus cor rolling the said live air leak ports and the main exha s ports, whereby the valve is actuated alte aate v in opposite directions by pressure fluid under working pressure through said kicker ports, which are also constant 5 open to atmosphere through said atmospheric leak ports, and the valve is held in one position or the other by live air admitted through one or the other of said live air leak ports.

In testimony specification.

CHARLES C. HAhSEN.

whereof I have signed this 

